How to Install Oracle Database 18c on CentOS 7

Install Oracle Database 18c on CentOS 7

Oracle Database 18c is latest version of Oracle Relational Database Management System or RDBMS, is a multi-model database. Oracle Database is commonly used in Online Transaction Processing / OLTP and Data Warhousing / DW environments. Oracle Database 18c is also available on Public and Private Clouds, Exadata and On-premises systems.

In this article, we will install Oracle Database 18c on CentOS 7 on-premises server in Silent mode.

There are many good reading material is available, specially from Oracle Certification Professional / OCP preparation guides. However, we also recommend reading Beginning Oracle SQL: For Oracle Database 12c (PAID LINK) by Apress to have a third party perspective about Oracle Database 18c.


Table of Contents:

Install Oracle Database 18c on CentOS 7

System Specification:

We have provisioned a CentOS 7 virtual machine with following specifications:

  • CPU - 3.4 Ghz (2 Cores)
  • Memory - 2 GB
  • Storage - 60 GB
  • Hostname -
  • IP Address - /24
  • Operating System - CentOS 7.6


Configure Local DNS Resolver in CentOS 7:

To configure name resolution, we can either use a central DNS server or we can use local DNS resolver. To keep it simple, we are using local DNS resolver for our server.

Connect to using ssh as root user and execute following command.

# cat >> /etc/hosts << EOF
> oracle-01

Verify name resolution by using ping command.

# ping
PING ( 56(84) bytes of data.
64 bytes from ( icmp_seq=1 ttl=64 time=0.053 ms
64 bytes from ( icmp_seq=2 ttl=64 time=0.068 ms


Disable Transparent Hugepages in CentOS 7:

Transparent Hugepages can cause memory allocation delays during runtime. Therefore, to avoid performance issues, Oracle recommends to disable Transparent Hugepages before starting installation. Oracle recommends that we instead use Standard Hugepages for enhanced performance.

Verify that Transparent Hugepages are enabled on our CentOS 7 server.

# cat /sys/kernel/mm/transparent_hugepage/enabled
[always] madvise never

The [always] flag shows that the Transparent Hugepages are in used by our CentOS 7 server.

To disable Transparent Hugepages we have to edit GRUB configuration.

# vi /etc/default/grub

Look for GRUB_CMDLINE_LINUX and add transparent_hugepage=never at the end. After editing this directive should be looks like as follows.

GRUB_CMDLINE_LINUX=" rhgb quiet transparent_hugepage=never"

Generate /etc/grub.cfg file using modified configurations.

# grub2-mkconfig -o /boot/grub2/grub.cfg
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-3.10.0-957.el7.x86_64
Found initrd image: /boot/initramfs-3.10.0-957.el7.x86_64.img
Found linux image: /boot/vmlinuz-0-rescue-07fcd178406f4b3ca09084082364afba
Found initrd image: /boot/initramfs-0-rescue-07fcd178406f4b3ca09084082364afba.img

Reboot the machine to verify configurations.

# systemctl reboot

After reboot, check status of Transparent HugePages again.

# cat /sys/kernel/mm/transparent_hugepage/enabled
always madvise [never]

Transparent Hugepages has been disabled.


Install Oracle Database 18c Prerequisite Packages on CentOS 7:

Install prerequisite software packages using yum command.

# yum install -y bc binutils compat-libcap1 compat-libstdc++-33 glibc glibc-devel ksh libaio libaio-devel libX11 libXau libXi libXtst libXrender-devel libXrender libgcc libstdc++ libstdc++-devel libxcb make smartmontools sysstat net-tools nfs-utils gcc-c++


Create Oracle Database 18c User and Groups:

Create OS users and groups as required by Oracle Database 18c.

# groupadd -g 1501 oinstall
# groupadd -g 1502 dba
# groupadd -g 1503 oper
# groupadd -g 1504 backupdba
# groupadd -g 1505 dgdba
# groupadd -g 1506 kmdba
# groupadd -g 1507 racdba
# useradd -u 1501 -g oinstall -G dba,oper,backupdba,dgdba,kmdba,racdba oracle
# echo "oracle" | passwd oracle --stdin
Changing password for user oracle.
passwd: all authentication tokens updated successfully.


Set Security Limits for Oracle User in CentOS 7:

Execute following command to set security limits for oracle user.

# cat >> /etc/security/limits.d/30-oracle.conf << EOF
> oracle   soft   nofile    1024
> oracle   hard   nofile    65536
> oracle   soft   nproc    16384
> oracle   hard   nproc    16384
> oracle   soft   stack    10240
> oracle   hard   stack    32768
> oracle   hard   memlock    134217728
> oracle   soft   memlock    134217728


Adjust Kernel Parameters in CentOS 7:

Set following Kernel parameters as required by Oracle Database 18c.

# cat >> /etc/sysctl.d/98-oracle.conf << EOF
> fs.file-max = 6815744
> kernel.sem = 250 32000 100 128
> kernel.shmmni = 4096
> kernel.shmall = 1073741824
> kernel.shmmax = 4398046511104
> kernel.panic_on_oops = 1
> net.core.rmem_default = 262144
> net.core.rmem_max = 4194304
> net.core.wmem_default = 262144
> net.core.wmem_max = 1048576
> net.ipv4.conf.all.rp_filter = 2
> net.ipv4.conf.default.rp_filter = 2
> fs.aio-max-nr = 1048576
> net.ipv4.ip_local_port_range = 9000 65500
# sysctl -p


Adjust SELinux Mode in CentOS 7:

Set SELinux to Permissive mode.

# sed -i 's/^SELINUX=.*/SELINUX=permissive/g' /etc/sysconfig/selinux
# setenforce permissive


Open Service Ports in CentOS 7 Firewall:

Allow Oracle SQL* Net Listener port 1521/tcp in Linux Firewall.

# firewall-cmd --permanent --add-port=1521/tcp
# firewall-cmd --reload


Create Directories for Oracle Database 18c:

We are using following two directories, One for the RDBMS software and other for the Oracle Databases.

# mkdir -p /u01/app/oracle/product/18.3.0/dbhome_1
# mkdir -p /u02/oradata
# chown -R oracle:oinstall /u01 /u02
# chmod -R 775 /u01 /u02


Set Environment Variables in CentOS 7:

Use following commands to set environment variables for oracle user.

# su - oracle
$ cat >> ~/.bash_profile << EOF
> # Oracle Settings
> export TMP=/tmp
> export TMPDIR=$TMP
> export
> export ORACLE_UNQNAME=cdb1
> export ORACLE_BASE=/u01/app/oracle
> export ORACLE_HOME=$ORACLE_BASE/product/18.3.0/dbhome_1
> export ORA_INVENTORY=/u01/app/oraInventory
> export ORACLE_SID=cdb1
> export PDB_NAME=pdb1
> export DATA_DIR=/u02/oradata
> export PATH=$ORACLE_HOME/bin:$PATH
> export LD_LIBRARY_PATH=$ORACLE_HOME/lib:/lib:/usr/lib
> export CLASSPATH=$ORACLE_HOME/jlib:$ORACLE_HOME/rdbms/jlib


Installing Oracle Database 18c on CentOS 7 in Silent Mode:

We have downloaded Oracle Database 18c (18.3) for Linux from Oracle website and transferred the zip file to our CentOS 7 virtual machine using WinSCP.

Switch to oracle user and unzip downloaded zip file.

# su - oracle
# unzip -d $ORACLE_HOME

Start Oracle Database 18c installation in Silent mode.

$ ./runInstaller -ignorePrereq -waitforcompletion -silent \
> oracle.install.option=INSTALL_DB_SWONLY \
> UNIX_GROUP_NAME=oinstall \
> oracle.install.db.InstallEdition=EE \
> oracle.install.db.OSDBA_GROUP=dba \
> oracle.install.db.OSBACKUPDBA_GROUP=backupdba \
> oracle.install.db.OSDGDBA_GROUP=dgdba \
> oracle.install.db.OSKMDBA_GROUP=kmdba \
> oracle.install.db.OSRACDBA_GROUP=racdba \
Launching Oracle Database Setup Wizard...

[WARNING] [INS-13014] Target environment does not meet some optional requirements.
   CAUSE: Some of the optional prerequisites are not met. See logs for details. installActions2019-03-20_10-26-13PM.log
   ACTION: Identify the list of failed prerequisite checks from the log: installActions2019-03-20_10-26-13PM.log. Then either from the log file or from installation manual find the appropriate configuration to meet the prerequisites and fix it manually.
The response file for this session can be found at:

You can find the log of this install session at:

As a root user, execute the following script(s):
        1. /u01/app/oraInventory/
        2. /u01/app/oracle/product/18.3.0/dbhome_1/

Execute /u01/app/oraInventory/ on the following nodes:
Execute /u01/app/oracle/product/18.3.0/dbhome_1/ on the following nodes:

Successfully Setup Software with warning(s).
Moved the install session logs to:

Oracle Universal Installer is giving warning because we are installing on a system with 2 GB RAM, whereas Oracle recommends at least 8 GB RAM for Oracle Database 18c installation. Therefore, you can safely ignore this warning.

Oracle Database 18c has been installed. Now connect as root user and execute the post-installation scripts.

# /u01/app/oraInventory/
Changing permissions of /u01/app/oraInventory.
Adding read,write permissions for group.
Removing read,write,execute permissions for world.

Changing groupname of /u01/app/oraInventory to oinstall.
The execution of the script is complete.
# /u01/app/oracle/product/18.3.0/dbhome_1/
Check /u01/app/oracle/product/18.3.0/dbhome_1/install/root_oracle-01.centlinux.com_2019-03-20_22-42-29-680074976.log for the output of root script


Create Oracle 18c Multitenant Database in Silent Mode:

Manually start default Oracle Listener.

$ lsnrctl start

LSNRCTL for Linux: Version - Production on 20-MAR-2019 22:47:53

Copyright (c) 1991, 2018, Oracle.  All rights reserved.

Starting /u01/app/oracle/product/18.3.0/dbhome_1/bin/tnslsnr: please wait...

TNSLSNR for Linux: Version - Production
Log messages written to /u01/app/oracle/diag/tnslsnr/oracle-01/listener/alert/log.xml

Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
Alias                     LISTENER
Version                   TNSLSNR for Linux: Version - Production
Start Date                20-MAR-2019 22:47:53
Uptime                    0 days 0 hr. 0 min. 1 sec
Trace Level               off
Security                  ON: Local OS Authentication
SNMP                      OFF
Listener Log File         /u01/app/oracle/diag/tnslsnr/oracle-01/listener/alert/log.xml
Listening Endpoints Summary...
The listener supports no services
The command completed successfully

Create an Oracle 18c Multitenant Database in Silent mode as follows.

$ dbca -silent -createDatabase \
> -templateName General_Purpose.dbc \
> -gdbname ${ORACLE_SID} -sid  ${ORACLE_SID} \
> -responseFile NO_VALUE \
> -characterSet AL32UTF8 \
> -sysPassword 123 \
> -systemPassword 123 \
> -createAsContainerDatabase true \
> -numberOfPDBs 1 \
> -pdbName ${PDB_NAME} \
> -pdbAdminPassword 123 \
> -databaseType MULTIPURPOSE \
> -automaticMemoryManagement false \
> -totalMemory 800 \
> -storageType FS \
> -datafileDestination "${DATA_DIR}" \
> -redoLogFileSize 50 \
> -emConfiguration NONE \
> -ignorePreReqs
[WARNING] [DBT-06208] The 'SYS' password entered does not conform to the Oracle recommended standards.
a. Oracle recommends that the password entered should be at least 8 characters in length, contain at least 1 uppercase character, 1 lower case character and 1 digit [0-9].
b.The password entered is a keyword that Oracle does not recommend to be used as password
   ACTION: Specify a strong password. If required refer Oracle documentation for guidelines.
[WARNING] [DBT-06208] The 'SYSTEM' password entered does not conform to the Oracle recommended standards.
a. Oracle recommends that the password entered should be at least 8 characters in length, contain at least 1 uppercase character, 1 lower case character and 1 digit [0-9].
b.The password entered is a keyword that Oracle does not recommend to be used as password
   ACTION: Specify a strong password. If required refer Oracle documentation for guidelines.
[WARNING] [DBT-06208] The 'PDBADMIN' password entered does not conform to the Oracle recommended standards.
a. Oracle recommends that the password entered should be at least 8 characters in length, contain at least 1 uppercase character, 1 lower case character and 1 digit [0-9].
b.The password entered is a keyword that Oracle does not recommend to be used as password
   ACTION: Specify a strong password. If required refer Oracle documentation for guidelines.
Prepare for db operation
8% complete
Copying database files
31% complete
Creating and starting Oracle instance
32% complete
36% complete
40% complete
43% complete
46% complete
Completing Database Creation
51% complete
53% complete
54% complete
Creating Pluggable Databases
58% complete
77% complete
Executing Post Configuration Actions
100% complete
Database creation complete. For details check the logfiles at:
Database Information:
Global Database Name:cdb1
System Identifier(SID):cdb1
Look at the log file "/u01/app/oracle/cfgtoollogs/dbca/cdb1/cdb1.log" for further details.

We have set a simple password, therefore dbca is giving us warnings.

Connect as root and execute following command to enable auto restart of CDB1 database.

# sed -i 's/:N$/:Y/g' /etc/oratab

Connect to CDB1 using sqlplus and enable Oracle Managed Files (OMF).

$ sqlplus / as sysdba

SQL*Plus: Release - Production on Wed Mar 20 23:56:25 2019

Copyright (c) 1982, 2018, Oracle.  All rights reserved.

Connected to:
Oracle Database 18c Enterprise Edition Release - Production


System altered.

Alter PDB1 so it will be open automatically at the time of database startup of CDB1 Database.


Pluggable database altered.


Autostart Oracle 18c Database and Listener in CentOS 7:

To autostart Oracle 18c Database and Listener we must create a systemd service as follows:

# vi /usr/lib/systemd/system/dbora.service

And add following directives therein.

Description=Oracle Database Service
ExecStart=/u01/app/oracle/product/18.3.0/dbhome_1/bin/dbstart /u01/app/oracle/product/18.3.0/dbhome_1
ExecStop=/u01/app/oracle/product/18.3.0/dbhome_1/bin/dbshut /u01/app/oracle/product/18.3.0/dbhome_1

Start and enable dbora.service.

# systemctl daemon-reload
# systemctl enable dbora.service
Created symlink from /etc/systemd/system/ to /usr/lib/systemd/system/dbora.service.
# systemctl start dbora.service
# systemctl status dbora.service
â dbora.service - Oracle Database Service
   Loaded: loaded (/usr/lib/systemd/system/dbora.service; disabled; vendor preset: disabled)
   Active: active (running) since Thu 2019-03-21 09:13:28 PKT; 1min 31s ago
  Process: 12004 ExecStart=/u01/app/oracle/product/18.3.0/dbhome_1/bin/dbstart /u01/app/oracle/product/18.3.0/dbhome_1 (code=exited, status=0/SUCCESS)
 Main PID: 10315 (code=exited, status=0/SUCCESS)
   CGroup: /system.slice/dbora.service
           ââ12017 /u01/app/oracle/product/18.3.0/dbhome_1/bin/tnslsnr LISTEN...
           ââ12505 ora_mz04_cdb1
           ââ12507 ora_q005_cdb1
           ââ12513 ora_mz03_cdb1
           ââ12553 ora_qm03_cdb1

Mar 21 09:12:55 systemd[1]: Starting Oracle Database Se...
Mar 21 09:12:55 dbstart[12004]: Processing Database ins...
Mar 21 09:13:28 systemd[1]: Started Oracle Database Ser...
Hint: Some lines were ellipsized, use -l to show in full.

We have successfully installed Oracle Database 18c on CentOS 7 server.



  2. work perfectly on my vmware vm ....ty man

  3. how do you connect to this new oracle db remotely?

  4. Very helpful guide. Thank you! God bless you!

  5. HI
    I am getting the below Error. Please help me.

    [oracle@oracledb ~]$ lsnrctl start
    -bash: lsnrctl: command not found
    [oracle@oracledb ~]$

    1. Looks the command path is not included in PATH environment variable. Try Following commands.

      export PATH=/u01/app/oracle/product/18.3.0/dbhome_1/bin/:$PATH
      echo "export PATH=/u01/app/oracle/product/18.3.0/dbhome_1/bin/:$PATH" >> ~/.bash_profile
      lsnrctl start

    2. Thanks you very much. It is working fine.

      But i want to manage DB through remotely . Could you tell me which oracle database client is best and also open source


    3. Please use Oracle Database Client.

  6. On Doing DBCA createDatabase I get following error :

    8% complete
    Copying database files
    9% complete
    [WARNING] ORA-00821: Specified value of sga_target 600M is too small, needs to be at least 3092M
    ORA-01078: failure in processing system parameters

    [FATAL] ORA-01034: ORACLE not available

    31% complete
    100% complete
    [FATAL] ORA-01034: ORACLE not available

    I followed each and every step of the document. Kindly guide.

    1. Please share the command that you have used for database creation.

  7. Hello Ahmer Mansoor, when i come to the point to do the silent install via commandline i get a [Warning] [INS-08101] unexpected failure in status "supportedOSCheck" but the only additional information is - java.lang.NullPointerException and the silent install is halted.
    Do you have any idea what the problem could be? Thank you - Rudolf

    1. Hi, the error seems to be due to an unsupported operating system.

      Please check your Operating System certification for the Oracle database 18c at Oracle Support website.

  8. Thank you for your reply - i tried with CentOS 8 - Best Regards - Rudolf

  9. Great tutorial. Thank you. Everything works on OL7

  10. The link to the oracle download is broken. Is the RPM good enough?

    1. Yes, the RPM is good enough but it is no longer available for free download.

      According to Oracle:

      "Oracle Database Enterprise Edition 10.2, 11.x, 12.x, and 18c are available as a media or FTP request for those customers who own a valid Oracle Database product license for any edition."

  11. Can these same steps be used to install Oracle 18c on RHEL 7.9?

Previous Post Next Post